1. Technical Field
The present invention relates to train monitoring equipment, and more particularly to train monitoring equipment enabling the location of a single car to be identified even when a plurality of trains of fixed formations are coupled together.
2. Prior Art
FIG. 1 is a block diagram showing the constitution of train monitoring equipment as shown, for example, on page 496 of "The 19th Transactions of Domestic Symposium on Cybernetics Utilization in Railway Engineering". In the figure, the reference numerals 101 to 108 denote monitoring stations which are respectively in each of the cars numbered 1 to 8. These monitoring stations are connected serially by transmission lines L. These eight cars form a train of fixed formation. The numeral 110 denotes a display unit connected to monitoring station 101 which is mounted in car No. 1, and the numeral 111 a display unit connected to monitoring station 108 mounted in car No. 8.
Because the prior art train monitoring equipment is constituted in the manner described above, that one of monitoring stations 101 or 108 which is mounted in the leading car operates as the control station for transmission control.
Assuming that car No. 1 located at the left end of the train shown in FIG. 1 is the leading car, monitoring station 101 serves as the master control station and monitoring stations 102 to 108 are the slave stations. Monitoring station 101 then interrogates monitoring stations 102 to 108 in sequence through transmission lines L, and collects and edits the information from each of monitoring stations 102 to 108, displaying it on display unit 110. The same information is also displayed on display unit 111 in a suitable way.
Since the station number (for example, one of the series 1 to 8 corresponding to the location of the cars) has been set in advance in each of monitoring stations 101 to 108 by a switch (not shown in the figure), monitoring stations 102 to 108 send back a response (i.e. information on the state of the car in which each monitoring station is mounted) to monitoring station 101, only when the station number of each monitoring station is designated by control station 101, demanding a reply from the designated station. In this case, since each car is assumed to be arranged in the form of the fixed train formation, that is to say, according to the order of the location of each car, it is possible to identify the position of the cars in the fixed formation in which monitoring stations 101 to 108 are mounted.
As described above, since the prior art train monitoring equipment determines the station numbers of the respective monitoring stations 101 to 108 by setting the station numbers to correspond to the location of the respective cars, when a plurality of trains of fixed formation are coupled together for use on a particular route, there are a plurality of monitoring stations having the same station number. This causes a problem of difficulty in transmitting and receiving information between the control station and the slave stations, and in correctly identifying the position of each of the cars which carry the monitoring stations.